杂交型马鞍网壳结构参数化设计及形状优化

摘要

杂交型网壳可以发挥各单一传统网壳的优点,在增大跨度的同时又可获得较高的经济效益.文章根据杂交型马鞍型网壳结构特点,采用APDL参数化设计语言研制了两类六种不同杂交型马鞍网壳参数化设计宏程序,运用ANSYS软件对其进行受力性能分析,并对受力性能最好的凯威特—联方(Kie-Lam)网壳进行了108种工况形状优化设计.结果表明:在同等工况下六种杂交型马鞍网壳中Kie-Lam最大位移为6.9 mm和最不应力为25.1 MPa均最小,受力最为合理;矢高f与网壳最不利应力成反比,f每增加1 m最不利应力平均下降幅度最大为0.51 MPa,随Ns变化没有统一规律;在S=60 m、f=30 m不变的情况下,存在一种工况Kn=8、Nx=12和Ns=8满足结构强度、刚度和稳定性前提下,使网壳结构总耗钢量最轻.%Hybrid shell can take the advantages of each single traditional shell,which can not only increase the span but also obtain higher economic benefits at the same time. Macro program of six kinds hybrid saddle reticulated shell parametric design were developed by ANSYS parameter of design language according to saddle reticulated shell features. The mechanical performances were analyzed and the shape optimization under 108 kinds of working condition for Kiewitt-Lamella Saddle Reticulated Shell was studied with objective function of minimum steel consumption and shape optimization design variables Kn( ring to symmetric regional copies number ),Nx( radial node ring number),Ns( the upper structure of radial ring). The results showed:The maximal displacement and the most unfavorable stress of Kiewitt-Lamella were 6. 9 mm and 25. 1 Mpa,which were the least of six kinds hybrid saddle reticulated shell that its mechanical performance was the most reasonable under the same condition. The vector height f was inversely proportional to the most unfavorable stress,existing suitable f made their respective overall deflection minimum,and Ns changed the law of the unity on both;When span S=60 m and the f=30 m were certain,existing one kind of working condition of Kn=8,Nx=12 and Ns=8 under the precondition satisfied the strength,stiffness and stability,making the total steel consumption of reticulated shell lightest.